# -*- coding: utf-8 -*-#
#-------------------------------------------------------------------------------
# 建立者:        潘炎珍  
# Name:         hw04
# Description:
# Author:       98745
# Date:         2019/1/17
#-------------------------------------------------------------------------------

while True:
    expression= input("请输入表达式：")
    if expression == "end":
        break;
    print("计算结果：",eval(expression))